Check-bolt oe doob



ALBERT BINGHAM, OF BOSTON, MASSACHUSETTS.

CHECK-BOLT OF DOOR LOCKS 0R LATCHES.

Specification forming part of Letters Patent No. 2,819, dated October 17, 1842; Reissued July 8,

TocZZ whom 'it may concern Be it known that I, ALBERT BINGHAM, of the city of Boston, in the county of Suffolk and Commonwealth of Massachusetts, have invented a new and useful Improvement in the Construction of Door-Locks; and I do hereby declarev that the following is a full and exact description thereof, reference being had to the accompanying drawings.

The nature of my invention consists in applying a check bolt to the knob on the in side of the door, in such a manner that the same will intercept the latch bolt, and thus operate as a fastening, the said check bolt being movable by a key or otherwise.

To enable others skilled in the art,to make and use my invention, I will proceed to describe its construction and operation.

Figure 1, shows the form of the latch bolt with what I call a thumb rod passing through its inner end, as at cn and a place or cavity for the spiral spring.

Fig. 2, shows the form of an iron case in which the latch bolt and spring are to be placed, the form of the face plate through which the beveled end of the bolt projects and the manner of uniting these two pieces, as at o. At C the edge of the case is cut and bent inward to prevent the bolt from sliding `too far in; at cl it is also so cut and bent as to form a rest for the inner end of the spring the bending being done after the bolt is inserted in the case. These parts, viz., the bolt, the case and the spring, when put together, are to be inserted in a proper sized mortise in the edge of the door, and then the thumb rod is to be driven through the same being long enough to project about one inch on each side of the door, and mov,- able in a horizontal slot'cut in the door. Fig. 3, is the form of the inside knob, flanched at the base, and having a slot eX- tending from its periphery y toward the center, as at c,-through which the thumb rod may pass, and move horizontally the requisite distance. At j' the tlanch is dis continued, for the purpose of affording a place to connect or insert the key plate and allow the check bolt hereafter described its proper motion.

F L his the key plate, ianched like the knob, and having more or less wards fitting the` key.

Fig. 5, shows the form of the check bolt, with a little knob or handle by which it may be moved without the use of the key, and which gives the lock the essential qualities of a night lock.

Fig. G, represents the combination of the foregoing parts, in the relative position they maintain when applied to the door. At g the thumb rod passes through the base or flat part of the knob. At tt is a flat spring` bearing on the check bolt, to prevent its inovingtoo easily, or by its own weight. At c' is that part of the check bolt, which, when moved by the key or handle passes behind the thumb rod and intercepts its motion. is the small knob or handle attached to the check bolt, by which it may be moved without the key.- At Z is an opening in the key plate through which this knob or handle passes. At m is a notch in the long arm of the check bolt, (which here projects beyond the periphery of the knob,) in which the lever of the keytakes its hold. At n is the center `of the key plate, where a stem, or a hole (as here re'presentech) will guide the ke-y to its wards and g'iilre its lever the proper hold of the check The knob and key plate, it will be understood, are to be attached to the door by screws, and require no cutting of the door except for the key hole.

The advantages of a lock and latch so constructed and connected, are the great diminution of friction and the consequent durability of the article. The spring not being required to overcome the friction of movable knobs, and a tumbler, may be so delicate that the gcntlest closing of the door will -serve to fasten it. It requires less cutting of the door, and consequently may be more readily applied.

That- I claim as my invention, and desire to secure by Letters Patent, is*

The application of a chec'k bolt, movable by a key, to the knob in the manner and for the purposes above substantially set forth.

ALBERT BINGHAM.

Witnesses:

IsAAo O. BARNES, LEMUEL "WILLIAMs [Fins'r PRINTED 1913.] 

